Light bars or emergency lights of the type used on emergency vehicles such as fire trucks, police cars, and ambulances, utilize warning signal lights to produce a variety of light signals. These light signals involve the use of various colors and patterns. Generally, these warning signal lights consist of incandescent and halogen light sources having reflective back support members and colored filters.
Many problems exist with the known methods for producing warning light signals. One particular problem with known light sources is their reliance on mechanical components to revolve or oscillate the lamps to produce the desired light signal. Additionally, these components increase the size of the light bar or emergency lights which may adversely affect the vehicle's aerodynamic characteristics. Moreover, because of the relatively poor reliability of conventional lighting and the complexity of the present strobe rotational systems there is an increased likelihood that a breakdown of the light bar or light source will occur requiring the repair or replacement of the defective component. Finally, conventional light bars and light sources require a relatively large amount of electrical current during operation. The demands upon the electrical power system for a vehicle may therefore exceed available electrical resources reducing optimization of performance or worse, generating a potential hazard from shorted or over-heated systems.
Halogen lamps or gaseous discharge xenon lamps generally emanate large amounts of heat which is difficult to dissipate from a sealed light enclosure or emergency light and which may damage the electronic circuitry contained therein. In addition, these lamps consume large amounts of current requiring a large power supply, battery, or electrical source which may be especially problematic for use with a vehicle. These lamps also generate substantial electromagnetic emissions which may interfere with radio communications for a vehicle. Finally, these lamps, which are not rugged, have relatively short life cycles necessitating frequent replacement.
Another problem with the known warning signal lights is the use of filters to produce a desired color. Filtering techniques produce more heat that must be dissipated. Moreover, changing the color of a light source requires the physical removal of the filter from the light source or emergency light and the replacement with a new filter. Furthermore, filters fade or flake over time rendering the filters unable to consistently produce a desired color for observation in an emergency situation.
These problems associated with traditional signaling lamps are exacerbated by the fact that creating multiple light signals requires multiple signaling lamps. Further, there is little flexibility in modifying the light signal created by a lamp. For example, changing a stationary lamp into one that rotates or oscillates would require a substantial modification to the light bar or light source which may not be physically or economically possible.
The present invention generally relates to electrical lamps and to high brightness light-emitting diode or “LED” technology which operates to replace gaseous discharge or incandescent lamps as used with vehicle warning signal light sources.
In the past, the xenon gaseous discharge lamps have utilized a sealed compartment, usually a gas tube, which may have been filled with a particular gas known to have good illuminating characteristics. One such gas used for this purpose was xenon gas, which provides illumination when it becomes ionized by the appropriate voltage application. Xenon gas discharge lamps are used in the automotive industry to provide high intensity lighting and are used on emergency vehicles to provide a visible emergency signal light.
A xenon gas discharge lamp usually comprises a gas-filled tube which has an anode element at one end and a cathode element at the other end, with both ends of the tube being sealed. The anode and cathode elements each have an electrical conductor attached, which passes through the sealed gas end of the lamp exterior. An ionizing trigger wire is typically wound in a helical manner about the exterior of the glass tube, and this wire is connected to a high voltage power source typically on the order of 10-12 kilowatts (kw). The anode and cathode connections are connected to a lower level voltage source which is sufficient to maintain illumination of the lamp once the interior gas has been ionized by the high voltage source. The gas remains ignited until the anode/cathode voltage is removed; and once the gas ionization is stopped, the lamp may be ignited again by reapplying the anode/cathode voltage and reapplying the high voltage to the trigger wire via a voltage pulse.
Xenon gas lamps are frequently made from glass tubes which are formed into semicircular loops to increase the relative light intensity from the lamp while maintaining a relatively small form factor. These lamps generate extremely high heat intensity, and therefore, require positioning of the lamps so as to not cause heat buildup in nearby components. The glass tube of a xenon lamp is usually mounted on a light-based pedestal which is sized to fit into an opening in the light fixture and to hold the heat generating tube surface in a light fixture compartment which is separated from other interior compartment surfaces or components. In a vehicle application, the light and base pedestal are typically sized to fit through an opening in the light fixture which is about 1 inch in diameter. The light fixture component may have a glass or plastic cover made from colored material so as to produce a colored lighting effect when the lamp is ignited. Xenon gas discharge lamps naturally produce white light, which may be modified to produce a colored light, of lesser intensity, by placing the xenon lamp in a fixture having a colored lens. The glass tube of the xenon lamp may also be painted or otherwise colored to produce a similar result, although the light illumination from the tube tends to dominate the coloring; and the light may actually have a colored tint appearance rather than a solid colored light. The color blue is particularly hard to produce in this manner.
Because a preferred use of xenon lamps is in connection with emergency vehicles, it is particularly important that the lamp be capable of producing intense coloring associated with emergency vehicles, i.e., red, blue, amber, green, and clear.
When xenon lamps are mounted in vehicles, some care must be taken to reduce the corroding effects of water and various chemicals, including road salt, which might contaminate the light fixture. Corrosive effects may destroy the trigger wire and the wire contacts leading to the anode and cathode. Corrosion is enhanced because of the high heat generating characteristics of the lamp which may heat the air inside the lamp fixture when the lamp is in use, and this heated air may condense when the lamp is off resulting in moisture buildup inside the fixture. The buildup of moisture may result in the shorting out of the electrical wires and degrade the performance of the emission wire, sometimes preventing proper ionization of the gas within the xenon gas discharge lamp.
Another problem with the known warning signal lights is the use of rotational and/or oscillating mechanisms which are utilized to impart a rotational or oscillating movement to a light source for observation during emergency situations. These mechanical devices are frequently cumbersome and difficult to incorporate and couple onto various locations about a vehicle due to the size of the device. These mechanical devices also frequently require a relatively large power source to impart rotational and/or oscillating movement for a light source.
Another problem with the known warning signal lights is the absence of flexibility for the provision of variable intensity for the light sources to increase the number of available distinct and independent visual light effects. In certain situations it may be desirable to provide variable intensity for a light signal, or a modulated intensity for a light signal, to provide a unique light effect to facilitate observation by an individual. In addition, the provision of a variable or modulated light intensity for a light signal may further enhance the ability to provide a unique desired light effect for observation by an individual.
No known warning light systems utilize a variable or modulated light intensity to modify a standard lighting effect nor do they have the design flexibility to easily make those changes. The warning lights as known are generally limited to a flashing light signal. Alternatively, other warning signal lights may provide a sequential illumination of light sources. No warning or utility light signals are known which simultaneously provide for modulated and/or variable light intensity for a known type of light signal to create a unique and desirable type of lighting effect.
No warning signal lights are known which provide irregular or random light intensity to a warning signal light to provide a desired lighting effect. Also, no warning light signals are known which provide a regular pattern of variable or modulated light intensity for a warning signal light to provide a desired type of lighting effect. It has also not been known to provide a warning light signal which combines either irregular variable light intensity or regular modulated light intensity to provide a unique and desired combination lighting effect.
It has also not been known to provide alternative colored LED light sources which may be electrically controlled for the provision of any desired pattern of light signal such as flashing, pulsating, oscillating, modulating, variable, rotational, alternating, strobe, sequential, and/or combination light effects. In this regard, a need exists to provide a spatially and electrically efficient LED light source for use on an emergency or utility vehicle which provides the appearance of rotation, or other types of light signals.
In view of the above, there is a need for a warning signal light that:                (1) Is capable of producing multiple light signals;        (2) Produces the appearance of a revolving or oscillating light signal without reliance upon mechanical components;        (3) Generates little heat;        (4) Uses substantially less electrical current;        (5) Produces significantly reduced amounts of electromagnetic emissions;        (6) Is rugged and has a long life cycle;        (7) Produces a truer light output color without the use of filters;        (8) Is positionable at a variety of locations about an emergency vehicle; and        (9) Provides variable light intensity to the light source.        
Other problems associated with the known warning signal lights relate to the restricted positioning of the signal light on a vehicle due to the size and shape of the light source. In the past, light sources due to the relatively large size of light bars or light sources, were required to be placed on the roof of a vehicle or at a location which did not interfere with, or obstruct, an operator's ability to visualize objects while seated in the interior of the vehicle. Light bars or light sources generally extended perpendicular to the longitudinal axis of a vehicle and were therefore more difficult to observe from the sides by an individual.
The ease of visualization of an emergency vehicle is a primary concern to emergency personnel regardless of the location of the observer. In the past, optimal observation of emergency lights has occurred when an individual was either directly in front of, or behind, an emergency vehicle. Observation from the sides, or at an acute angle relative to the sides, frequently resulted in reduced observation of emergency lights during an emergency situation. A need therefore exists to improve the observation of emergency lights for a vehicle regardless of the location of the observer. A need also exists to improve the flexibility of placement of emergency lights upon a vehicle for observation by individuals during emergency situations.
A need exists to reduce the size of light sources on an emergency vehicle and to improve the efficiency of the light sources particularly with respect to current draw and reduced aerodynamic drag. In addition, the flexibility for the positioning of the light sources about a vehicle is required to be enhanced in order to optimize utility for a warning signal light. In order to satisfy these and other needs, more spatially efficient light sources such as LED's are required.
In the past, illumination of an area to the front or to the sides of an emergency vehicle during low light conditions has been problematic. Take-down lights have been utilized by law enforcement personnel for a number of purposes including, but not necessarily limited to, enhancing observation of an individual in a vehicle on a roadway subject to investigation and to hide the location of an officer, or to block or deter observation of an officer by individuals during law enforcement activities.
A need exists for an LED take-down light which has significant illumination characteristics, is spatially efficient, has a long useful life, and has reduced current draw requirements for use on a law enforcement or utility vehicle.
The alley lights as known also suffer from the deficiencies as identified for the take-down lights during dark illumination conditions. Alley lights are used to illuminate areas adjacent to the sides of a vehicle.
In the past, the intersection clearing lights have been predominately formed of halogen, incandescent, and/or gaseous discharge xenon illumination sources. A need exists for an intersection clearing light which solves these and other identified problems.
A problem has also existed with respect to the use of emergency lights on unmarked law enforcement vehicles. In the past, emergency lights for unmarked law enforcement vehicles have consisted of dome devices which are formed of revolving mechanisms. These lights are usually withdrawn from a storage position under a motor vehicle seat for placement upon dashboard of a law enforcement vehicle. In undercover situations it has been relatively easy to identify dashboard affixation mechanisms used to secure these types of dome illumination devices to a dashboard. The known dome devices are also clumsy, have large current draw requirements, and are difficult to store in a convenient location for retrieval in an emergency situation by an individual. A need therefore exists for an emergency vehicle or utility warning light which is spatially efficient, easily hidden from view, and is transportable by an individual for retrieval during an emergency situation.
A need also exists for a new emergency vehicle light bar which is aerodynamic and which provides for both a longitudinal illumination element and an elevated pod illumination device.
In the past, emergency personnel, law enforcement officers, air traffic controllers, and/or pilots have utilized radio frequencies as a primary means of communication. One draw back associated with the use of radio frequency communication is the limited number of radio frequencies available for use within high density traffic areas where radio saturation may cause an unsafe condition through delayed communication and response during transmission of routine information. In addition, a number of available radio frequencies have been assigned for digital transmission further limiting the accessability and/or availability of transmission of routine information. Further, radio frequencies have generally not been available for certain applications including communication between motor vehicles and ground sources related to avionics such as approach lighting and/or taxi location identification.
Another problem associated the use of radio frequencies for communication of routine information is the material intensive nature of the transmitters and/or receivers. The radio frequency transmitters and receivers are generally expensive and further require a large power supply which is a concern for motor vehicle and/or aircraft applications. A need exists for additional avenues of relatively short range communication which do not utilize radio frequency transmissions. In general, cell phones and/or microwave communication are not viable communication alternatives and/or options due to the need for instantaneous communication and receipt of information without the necessity to identify, dial, connect, and couple to a receiver. A need therefore exists for use of an alternative communication source and/or carrier of information which is instantaneous and has high reliability with economical power consumption and material requirements.
In the past, attempts have been made to use light as a communication source normally associated with laser optics. In general, the use of laser optics as a communication source has raised a number of considerations related to performance, durability, and expense. Further, laser optic communication may be difficult to achieve due to the inflexibility of the lasers for transmission of both a directional and/or non-directional signal. The use of laser optics as a communication source has therefore not proven to be reliable, economical and/or viable for use in motor vehicle and avionics applications.
A need exists for a pulsed light signal for communication of information which is durable, reliable, and economical to an end user.
Federal Aviation Administration regulations require an anti-collision light system for placement on the fuselage of all aircraft. The rotating features of a dome light and/or flashing beacon include many of the same problems as earlier described related to size, durability, performance, current draw parameters, and ease of maintenance. In general, the light sources utilized within a rotating dome light or flashing beacon are not durable or efficient.
A need exists to replace the known illumination sources for a rotating dome light and/or flashing beacon as utilized within aircraft with modern LED light sources.
Radio frequency transmissions are regulated within the vicinity of an air field to eliminate and/or minimize risk of interference with air traffic communications. A need exists for alternative communication carriers for reduction of radio frequency communications within the vicinity of an airport. Due to human factors, in the past it has generally been quite difficult to instantaneously identify the exact location of aircraft adjacent to runways during taxiing.
As known, taxi ways of airports have generally utilized stationary lights, runway lights, and/or approach lights, which are not formed of LED technology. Therefore, the brightness, durability, and economics related to current draw have not been maximized to provide optimal performance for the known stationary lights, runway lights, and/or approach lights for an airport.
In the past it has not been known to use the stationary lights, runway lights, and/or approach lights as a communication source for the control of air traffic at an airport. Further, in the past an aircraft rotating exterior dome illumination source has not been used to simultaneously function as a communication device for the transmission and receipt of variable and/or pulsated light signals as generated from an LED light source. The variable and/or pulsed light signals may be alternatively described as the systematic information transfer through encrypted/pulsed light or acronym SIT-TEL. Further, it has not been know to use a variable and/or pulsating light signal or SIT-TEL communication, as generated from an anti-collision light, as an information courier through the use of LED technology.
The Federal Aviation Administration requires identification and collision avoidance systems to be operational at all times at all airports for regulation of ground and air traffic. No communication device is know which transmits an encrypted code within a light carrier for communication of information such as the proximity to a specific location, and/or for aircraft identification.
In the past, air traffic controllers have relied upon VFR or radar signals in order to identify the position of aircraft relative to a control tower. Air traffic controllers also utilize redundant VFR and/or radar systems as backup systems in the event of an initial systems failure. No economical and/or low power backup system to the VFR location indicators is generally available. The high power requirements and equipment expense of VFR radar systems, and the necessity for redundant backup systems, is quite costly for an airport. A further backup utilizing a communication system operating through recognition of pulsed light signals incorporating low power requirements may be extremely useful.
Radio frequency communications are frequently limited, in that there are a finite number of available radio frequencies for commercial and/or private use. The available radio frequency signals are also heavily regulated by the Federal Communications Commission. In a number of instances, the use of radio frequency transmissions may cause interference with a localized environment which in turn may adversely affect adjacent radio frequency transmitters. A benefit obtained from use of a light source as a communication carrier is that there are a virtually infinite number of available wavelengths for a light source. No device has been previously known which utilize LED technology to generate light signals used as a carrier of information for the replacement of radio transmissions, and as particularly used in association with vehicles and/or aircraft. In addition, no device is known which utilizes a light signal for transmission to a receiver which may then trigger audio and/or pre-stored information or convert information transmitted through the use of pulsed light into an audio signal.
A further problem with aircraft rotating illumination domes and/or flashing beacons is the failure of the illumination domes and/or flashing beacons to continue operations during emergency landing situations where the power for the aircraft is terminated. Due to the large power requirements for the rotating domes and/or flashing beacons, any power outage within the aircraft normally terminates the illumination of the rotating dome and/or flashing beacon. The power requirements for the rotating domes and/or flashing beacon illumination sources is generally sufficiently large to prohibit the transportation and use of additional battery sources for an aircraft during emergency landing situations. A need therefore exists for an emergency beacon light source which may continue to operate for an extended period of time, having low power consumption, which may be operated by a transported battery within an aircraft. An LED light source associated with the rotating light and/or exterior beacon therefore significantly improves the operation of the rotating beacon as an emergency beacon during emergency landing situations. Further, the low power requirements of the LED light source enable an exterior rotating light source and/or flashing beacon to operate for an extended period of time following a crash landing to signal the identification of a downed aircraft.
Needs continue to exist for the use of an LED illumination source and communication device for use on aircraft support vehicles, to enhance visual identification and location relative to an airport; to augment the proximity warning systems for aircraft and the regulation of air and ground traffic adjacent to an airport; to enhance the proximity and anti-collision warning light systems of towers for identification by aircraft; for the provision of economical and high brightness LED technology light sources for use in airport runway lighting, airport obstruction lighting, tower lighting, obstacle lighting, taxi lighting, and for use on aircraft as rotating domes and/or flashing beacons and/or landing lights.
Law enforcement officers in the past have generally been limited to visualization of a license plate for identification purposes. Upon visualization of a license plate, an officer may enter the observed license plate into a data base for identification of vehicle registration information. In the past, law enforcement personnel have also utilized optical aids such as focused optics and/or scopes to assist in the visualization and identification of license plates on moving vehicles. The optical and/or focused optic devices are generally expensive and may be extremely difficult to operate during moving conditions. Vehicles having the targeted license plates frequently change lanes and/or bounce upon uneven roadways rendering observation difficult.
No device is presently known which is inexpensive and which utilizes LED technology in association with a license plate, which includes the use of an LED transmitter and light receiver as coupled to a controller, to receive and transmit a pulsed LED light signal or SIT-TEL communication as a carrier of information to a law enforcement vehicle. No device is also known which minimizes environmental interference and accurately confirms the correct tagging, observation, and/or interrogation of a license plate by a law enforcement officer. Further, no backup device is known which supplements the confirmation system for verification of identification of a vehicle subject to consideration.
Another problem with the known law enforcement identification systems for vehicles is that law enforcement personnel are frequently required to place themselves within a certain proximity of a vehicle under observation. Proximity to a suspect vehicle significantly increases the likelihood of recognition of the location of the law enforcement personnel. Law enforcement personnel do not wish to place themselves in close proximity to a vehicle under consideration. Law enforcement personnel desire to be unobserved by suspects during law enforcement investigations and/or activities.
No communication device is known which may transmit license plate information such as the plate number, registered owner, make, model, and/or status of the license plate, to insure that a correct vehicle has been interrogated during police investigations. A need also exists to assists law enforcement officers in speed trap activities to confirm and verify the correct tagging of a target vehicle with radar and/or laser speed detection devices. No communication device is currently known which provides flexibility to select between a focused interrogation specific function versus a non-directional interrogation function for investigation of vehicles relative to a law enforcement officer through the use of LED technology. Further, no communication device is known which may simultaneously check and compare all license plates within the proximity of a law enforcement vehicle for a specific status such as a stolen vehicle identification through a continuous non-directional sweep of a transmitted LED light signal.
In the past, buoys have been used in marine applications to identify channels and hazards such as reefs, bars, rocks, and/or shallow water conditions. The warning buoys as known have frequently not included visual warning light signals. Alternatively, the known warning buoys have included visual warning light signals which have not been bright or rugged. These warning buoy light sources have suffered a relatively short life and have required a relatively large battery source. As such, the warning light signals used with marine buoys have not been efficient for signaling marine traffic. No marine buoy is known which utilizes LED technology to conserve power and to provide a durable and long useful life light source which may be operated on a relatively small battery and/or solar power source.
In addition, no marine buoy is known which incorporates an LED light source which contains a modulated and/or variable light controller which may simultaneously transmit a pulsed light signal or SIT-TEL communication to transmit information obviating the necessity for radio transmissions.
Currently each year a significant number of automobiles and other motor vehicles are involved in accidents with trains at railroad crossings. Frequently these accidents occur at railroad crossings in rural areas which are not marked with railroad crossing gates, warning bells, and/or flashing light signals. The absence of warning devices is frequently the result of economic considerations at remote and/or low traffic areas. A need exists for a warning light signal at remote railroad crossings which may be easily attached to an existing railroad crossing sign. Further, a need exists for a low power, battery powered, and/or solar powered light signal for use at remote railroad crossings which may be easily activated by an approaching train to warn traffic to reduce the likelihood of a vehicle/train collision.
In the past, emergency vehicles have used radio frequency transmissions to trigger intersection semaphores to switch to a green light signal to permit uninhibited passage of the emergency vehicle through the intersection. A problem with the radio frequency transmissions is the lack of available radio wavelengths, and the localized radio frequency interference, adjacent to intersections. In addition, the devices as known frequently have a large current consumption and are relatively expensive. The positioning and wiring of OPTICOM receiving and switching devices upon semaphores is generally elevated above an intersection, increasing initial construction expenses. The positioning of the OPTICOM receiving and switching devices, therefore renders maintenance and/or replacement problematic.
It has not been known to use light emitting diodes to provide a light signal to trigger an OPTICOM intersection clearing light. In addition, it has not been known to improve the useful life of an OPTICOM device through the use of long life rugged LED technology which may be operated by a low voltage power source such as a battery and/or solar power unit.
No device is known which provides simultaneous communication to a plurality of independently operated units of soldiers within a theater of operation which coordinates movement, actions, location of friendly troops, and/or identifies the location of hostile soldiers through the use of a pulsed light communication system. In this regard, no device is known which may have the dual functionality of a light source such as a flare in combination with a pulsed SIT-TEL communication system. As is known, radio communications within a theater of operation are frequently interrupted or terminated leaving units of troops without direction as to modified objectives. A need therefore exists for alternative sources of communication which do not rely upon radio transmissions for communication of orders and/or other types of critical information to soldiers engaged in hostilities. In addition, silence and the secretion of the location of troops within a theater of operations is frequently critical. Within situations necessitating silence, the use of radio transmissions is prohibited leaving soldiers without effective communications. A need therefore exists for an alternative source of communication for soldiers which is silent and which does not rely upon radio transmissions.